Two men already accused of accepting illegal kickbacks in a large federal health care fraud case have been arrested on unrelated drug smuggling charges after the FBI says they bought a Los Angeles medical marijuana business and sent large shipments of the drug to Dallas, according to federal court records.

Andrew Hillman, 42, and Semyon Narosov, 54, who are in the laboratory testing business, were arrested Friday and charged in federal court with distributing 100 kilograms or more of marijuana, a federal criminal complaint states. They have court appearances Tuesday.

The men are on pretrial release in connection with in a $200 million federal bribery and kickback case involving Forest Park Medical Center. In that case, the defendants are charged with conspiracy to pay and receive health care bribes and kickbacks. Prosecutors say the men received about $190,000 in bribes and kickbacks for referring patients to the now-defunct Dallas hospital.

That indictment was filed in November 2016. Hillman and Narosov were released the following month on several conditions, including that they not break the law. Prosecutors in that case have not as of Monday afternoon filed any motions to revoke their pretrial release.

Jay Ethington, an attorney for Narosov, said Monday he was still reviewing court records in the case.

"This development is a surprise to us and we're gonna prepare to deal with it in court in the near future," he said.

An attorney for Hillman could not be reached for comment.

The two men also are involved in a $100 million fraud lawsuit from an insurance company that alleges they paid bribes and kickbacks to drum up business.

Next Health offices in Dallas.

(Kevin Krause/Staff Photographer)

UnitedHealthcare says in its suit, filed in January 2017, that Next Health, a Dallas-based laboratory network controlled by Hillman and Narosov, paid millions in bribes and kickbacks to doctors and other providers for overpriced and unnecessary drug and genetic tests.

Next Health's sales consultants gave people $50 gift cards to urinate in cups at Whataburger bathrooms, the lawsuit says.

The drug conspiracy investigation began in June 2017 when the Dallas FBI got a tip from the Los Angeles County sheriff's office that Hillman and Narosov had bought a medical marijuana business in that city with a man named Allan Cohen, according to a federal complaint.

The men were shipping large loads of the drug to Dallas via Federal Express, according to the complaint.

Some of the drug shipments ended up at an office on Commerce Street in Deep Ellum, the complaint said.

The Los Angeles County sheriff's office intercepted packages in May 2017 containing more than 40 pounds of "high grade marijuana with a street value of more than $120,000," according to the complaint.

FBI agents in January and February conducted surveillance on Cohen as he picked up packages from the Commerce Street office, the complaint says. In one case, Cohen took the packages to an apartment building on Live Oak Street, the complaint says.

Cohen was not charged in the complaint.

In May, the FBI captured recordings of Cohen with the help of a "cooperating witness." In the recordings, Cohen talked about Hillman being upset about not being paid, the complaint says.

Agents on June 4 questioned Cohen, who told them that he, Hillman and Narosov were shipping marijuana to Texas from California for a profit, the complaint says.

"Further, Cohen described how he, and others, would provide cash from the sale of marijuana to Hillman and Narosov," the complaint said.

A man known in the complaint at "Person A" was part of the distribution chain, according to the complaint. He drove a 2008 Porsche SUV and helped Cohen pick up the packages, the complaint says.

Cohen agreed to record conversations he had with Hillman about being paid money that he, Hillman and Narosov were owed by Person A, the complaint said.

Agents watched as Cohen gave $10,000 in cash to Hillman and Narosov at a Starbucks at Forest Lane and Preston Road, according to the complaint. Narosov took the cash to his work office at 4100 Alpha Road, the complaint says. Cohen delivered another $12,000 in cash to Hillman at the Alpha Road office, the complaint says.